Zoned federation of game servers: a peer-to-peer approach to scalable multi-player online games

Today's Multi-player Online Games (MOGs) are challenged by infrastructure requirements, because of their server-centric nature. Peer-to-peer networks are an interesting alternative, if they can implement the set of functions that are traditionally performed by centralized authoritative servers. In this paper, we propose a zoned federation model to adapt MOG to peer-to-peer networks. In this model, zoning layer is inserted between the game program and peer-to-peer networks. We introduce the concept of zone and zone owner to MOG. Zone is some part of the whole game world, and zone owner is an authoritative server of a specific zone. According to the demands of the game program, each node actively changes its role to zone owner and works in the same way as a centralized authoritative server. By dividing the whole game world into several zones, workloads of the centralized authoritative game server can be distributed to a federation of nodes. We have implemented the zoned federation model, and evaluate it with a prototypical multi-player game. Evaluation results indicate that our proposed approach is applicable to small and medium-sized MOGs, where the number of nodes is less than 500.